CNN Worldwide President Jim Walton announced his decision to leave the cable network in an email to staff workers on Friday. Walton also told his staff that he will stay until the end of the year, while the company looks for a successor.

Walton’s announcement comes at a time its U.S. network is suffering from dismally poor ratings. The flagship American branch has fallen third to rivals Fox News Channel and MSNBC in prime time. Last month, the network was embarrassed after initially incorrectly reporting the Supreme Court’s decision regarding President Obama’s health care law.

A man who has worked at CNN since 1981, Walton said, “I think this company needs some new thinking. I’ve been doing this job I’m in now for 10 years and I’m ready for a change.”